The use of JavaScript can be listed like this

1. Checking and correcting the form data in the user side
2. Dynamically change the web page without reload it.
3. Create applications like calculator, simple applications and games.
4. Add effects to a web page which will attract more visitors

These are the important use of JavaScript. Some of them are very important, some of them not that much. Here I am showcasing some important JavaScript tools which commonly using in website.

JavaScript form validation

The most important and common functionality of a JavaScript is form validation. Most of the people using different JavaScript libraries such as Jquery, Moo tools, etc etc. As I am a fan of Jquery, I personally use bassistance JavaScript validation. It is simple to use and giving lot of options

Showcase image / video gallery

There are a lot of JavaScript libraries are available for showcasing images and videos even web pages. Here is the very popular JavaScript which used to overlay images / video / web page.

Lighbox

Lightbox is a simple, unobtrusive script used to overlay images on the current page. It’s a snap to setup and works on all modern browsers.

Thickbox

ThickBox is a webpage UI dialog widget written in JavaScript on top of the jQuery library. Its function is to show a single image, multiple images, inline content, iframed content, or content served through AJAX in a hybrid modal.

Greybox

GreyBox can be used to display websites, images and other content in a beautiful way.

shadow box

Shadowbox is an online media viewer application that supports all of the web’s most popular media publishing formats.

Highslide

Highslide JS is an open source image, media and gallery viewer written in JavaScript.

jcarousel

jCarousel is a jQuery plugin for controlling a list of items in horizontal or vertical order. The items, which can be static HTML content or loaded with (or without) AJAX, can be scrolled back and forth (with or without animation).

SWFobject

SWFObject is an easy-to-use and standards-friendly method to embed Flash content, which utilizes one small JavaScript file

Miscellaneous scripts

• Drop down menus
• Tab styles
• Pushup JavaScript

For integrating all these scripts, person requires only knowledge of basic html and JavaScript. If you are using some other tools please share with me through the comment form.